I REALLY think they are wrong about the Malawi Bloat diagnosis.
In regards to the UB forum: that specific diagnosis was given based on it "sounding like Malawai Bloat" during a conversation with a pharmaceutical rep - hardly a reliable source.
I really feel in 'Rusty's' case it was a last-ditch effort when all else failed.
I have tried clout to treat similar bloats in bettas - it killed them. If you want to try, use a 1/2 or 1/4 dose.
That's what has been bothering me BTW!

I haven't kept bettas in the last 4 years because of a transitional life-style & now living in an EXTREMELY hard-water area; but before that I was breeding & selling for a few years. I remember now towards the end of my 'career' having quite a few bloat cases. The only way I was able to prolong life in any of my bettas was through Antibiotic use. I now remember when I started using the antibiotic I got a VERY sharp decrease in the betta-deaths. However I was breeding show fish who are very fragile & with allot of these bettas, if they loose their breeding ability they were no long of monetary value to me so I didn't treat overly aggressively.
Obviously Agro is a pet & means allot to you, I applaud your interest in treating him!!

Chichlids are VERY far removed from anabatoids (bettas), it's like using a pig diagnosis on a cat.
In regards to the protozoan
Quote:
| ...but these appeared to be free-living organisms and not clinically significant. |
I'm sure they were just taking advantage of a sick fish and should not have been treated for.
No one is quite sure what Malawi Bloat is caused by but one of the best theories is that it is caused by parasite that for some reason gains hold on your fish. That would have been the reasoning behind prescribing the metro.
For more information on
Malawi Bloat.
That is quite concerning that Agro is also experiencing swim-bladder issues, that may well mean that his condition is very far advanced. Did he develop the 'sbd' first or second to the tumour growth? If he's got the same granular tissue growing it could be constricting him swim-bladder making it impossible for him to fill it properly.
OR
It may mean that he's just constipated!!

Stop feeding him anything for a day or two and give him some peas. You can do that along-side his medication.
Here is a good article:
Constipation
Providing him with a floating pad will give him a place to sit if he's not feeling well. Almond tree leaves (you'd have to get them online) or a lily pad are both good options.